Looking for new sway bar. Can I go too big??

We've been slowly upgrading my sons 70 Dart. So far we have 1.03 torsion bars, QA1 upper control arms with the extra caster built in and factory BBP disc. No shocks yet. Now I'm looking at a front bar. We don't have the tabbed lower arms so looking at a kit with bolt on tabs. I've narrowed it down to two bars from Hellwig. One is 1 1/8 dia. the other is 1 1/4. The 1 1/4 bar is offset a bit to accept wheels with up to 5.75 backspace which would be good for us as we have a 17" rim with 5 1/2 BS. My question being is the 1 1/4 bar too big? I could put up with a light rub on the bar from the tire at full lock. Should I stick with the 1 1/8?